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Headphone amp audio repair?

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So it seems my 789 is having some problems after about 2 years of using it. When I turn it on, the overcurrent protection light turns red, and never clicks over and turns to white. I tried opening it up in hopes of seeing a burned out capacitor or some easy smoking gun I could maybe replace myself, but I don't see anything like that. Unfortunately, that's about as far as my expertise in this situation goes, so unless someone has other ideas, I think I need to turn this thing over to get repaired.

I was wondering if anyone had any good experiences with people who do repairs for this sort of thing. When I checked locally in my area, all I found were posts for things like TV's and entertainment center kind of stuff, and nothing smaller like amps or dacs. If it makes any difference, I am in the DFW area in Texas.

Any ideas of suggestions would be appreciated as I am way out of my comfort zone here. Thanks!
 

Wes

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Not enough info in your post, so let's start with the 123s - who made the 789?
 

MakeMineVinyl

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I would call the manufacturer if you can to get a recommendation. Generally, in our amps, an overcurrent fault implies something like a shorted output device, especially if this happens with no signal.
 
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CrimeInPartner
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Not enough info in your post, so let's start with the 123s - who made the 789?
Sorry, I guess I thought that was an assumed. I am talking about the Drop THX AAA 789. I got it in the last batch before Massdrop rebranded all the future 789s to Drop.
 
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MakeMineVinyl

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I see that's a headphone amp. In that case, it could be almost anything.
 

restorer-john

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Has anyone got a schematic for the 789?

Here's @Amir's interior shot from the review way back:
1625695789029.png


"Overcurrent" could be a failed OPA-564 or a fault in the actual start-up delay/protection/DC sense circuitry itself.
 
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I checked the Drop community board and it sounds based on others' experiences that, while Drop is considered the manufacturer, they don't do any repairs themselves and won't do anything out of warranty. When asked about making recommendations on who could do repairs, they referred back to asking the community to chime in. Doesn't really give me much else to go on at this point.
 

restorer-john

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I checked the Drop community board and it sounds based on others' experiences that, while Drop is considered the manufacturer, they don't do any repairs themselves and won't do anything out of warranty. When asked about making recommendations on who could do repairs, they referred back to asking the community to chime in. Doesn't really give me much else to go on at this point.

Well, the least they can do is provide you with a schematic. That is a bare minimum IMO. Then we can troubleshoot it remotely.
 

MakeMineVinyl

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Well, the least they can do is provide you with a schematic. That is a bare minimum IMO. Then we can troubleshoot it remotely.
Looks to me that all that digital flipping-and-flooping and comparitor-ing could be done more easily/cleanly with a simple microcontroller
 
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Well, the least they can do is provide you with a schematic. That is a bare minimum IMO. Then we can troubleshoot it remotely.
I went ahead and opened a support request with Drop asking about repair options and for a copy of the schematic as well so I can try and find someone myself able to make the repairs if needed. I'll update once I get something back.

To all those that have posted so far, I appreciate your help in giving me a path to go down in figuring out what to do so my amp doesn't end up turning into a big paper weight.
 

MakeMineVinyl

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I went ahead and opened a support request with Drop asking about repair options and for a copy of the schematic as well so I can try and find someone myself able to make the repairs if needed. I'll update once I get something back.

To all those that have posted so far, I appreciate your help in giving me a path to go down in figuring out what to do so my amp doesn't end up turning into a big paper weight.
I wouldn't hold my breath for them to send a schematic; the main issue is liability - sending someone a schematic is tacit approval for the customer to open up the unit and possibly get shocked/start a fire. Still, I'd like to see the schematic too.
 
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I wouldn't hold my breath for them to send a schematic; the main issue is liability - sending someone a schematic is tacit approval for the customer to open up the unit and possibly get shocked/start a fire. Still, I'd like to see the schematic too.
Oh I get that. But I don't know what other options there are if the manufacturer isn't going to stand behind their product and make the repairs themselves for some fee, or even partner with other repair places to do the fixes. Suggesting that people with problems should ask the community for help and basically saying 'It's not my problem' is going to make me thing twice before I consider making another Drop purchase if this is the level of support I can expect if something goes wrong.
 

MakeMineVinyl

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Oh I get that. But I don't know what other options there are if the manufacturer isn't going to stand behind their product and make the repairs themselves for some fee, or even partner with other repair places to do the fixes. Suggesting that people with problems should ask the community for help and basically saying 'It's not my problem' is going to make me thing twice before I consider making another Drop purchase if this is the level of support I can expect if something goes wrong.
Yes, your experience is typical and maddening, and points to a sad state of affairs in some of the consumer electronics industry.
 

groovybassist

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Oh I get that. But I don't know what other options there are if the manufacturer isn't going to stand behind their product and make the repairs themselves for some fee, or even partner with other repair places to do the fixes. Suggesting that people with problems should ask the community for help and basically saying 'It's not my problem' is going to make me thing twice before I consider making another Drop purchase if this is the level of support I can expect if something goes wrong.
This is why I support vendors like @tomchr (Neurochrome and TCA). His products do cost more than some competitors, but he takes mfg very seriously, which minimizes problems, and I’m confident he’s there to stand behind/repair any products he manufactures. Admittedly he’s a single point of failure, but I’d rather roll the dice with that than try to sort through ownership of a problem and potentially end up trashing the device in question.
 

restorer-john

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This is why I support vendors like @tomchr (Neurochrome and TCA). His products do cost more than some competitors, but he takes mfg very seriously, which minimizes problems, and I’m confident he’s there to stand behind/repair any products he manufactures. Admittedly he’s a single point of failure, but I’d rather roll the dice with that than try to sort through ownership of a problem and potentially end up trashing the device in question.

Tom's headphone amplifiers could survive a nuclear blast and keep working. :)
 

DVDdoug

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I don't know what you paid for this, but the bad news is that modern electronics is rarely worth repairing. :( The good news is it often "lasts forever".

...Several years ago I was working for a particular small electronics company and one product had a small circuit board that would occasionally "wear out" or die. It was an expensive piece of equipment so it was worth replacing that small board, but not worth repairing the board. As I recall, the assembled board cost us about $30 USD. It was assembled/soldered by an outside contractor and it didn't take much test-time. But a repair might take about an hour of test/debug/repair repair time by a skilled technician (plus a little for parts) and that's a lot more expensive than building the new ones in (small) quantities on an assembly line with less-skilled labor.

The stuff built in high quantities in China has nearly zero labor cost, and they are buying parts in bulk so the parts are cheaper than what a repair shop would have to pay.
 

Bob-23

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The good news is it often "lasts forever".
Forever > 5 Yrs? :)

I'd say, through-hole components lasted 'forever' - failing resistors or capacitors practically didn't happen (except of really old electrolytic capacitors). In 'modern' surface-mount-electronics these failures occur regularly.
 

MakeMineVinyl

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Forever > 5 Yrs? :)

I'd say, through-hole components lasted 'forever' - failing resistors or capacitors practically didn't happen (except of really old electrolytic capacitors). In 'modern' surface-mount-electronics these failures occur regularly.
That is not been what I have seen in years of designing electronics which use surface mount parts (and through-hole for decades before that). There is no mechanism that is not also present in through hole parts which would lead to failure. If anything, surface mount PCBs are superior in terms of component compactness, i.e. it is a lot easier to design PCBs which manage things like grounds, power planes, and close coupling of critical components.

There is a lot of designed in obsolescence with today's products in with the use of software needing external updating, and in some cases not receiving those updates in order to keep them operating as they did when purchased. That is a 'failure' but it has nothing to do with the actual surface mount parts.

There are plenty of extremely reliable products using surface mount components such as computers and smart phones which will only stop working satisfactorily when software / firmware support is not longer available (or in the case of phones, they are abused to the point of failure).
 
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CrimeInPartner
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I got an initial reply from the Drop support person that basically said what had been stated prior that they don't do repairs, don't partner with anyone that they can point me to for repairs, and can't provide a schematic so I can find someone to do the repair, but he did get me a copy of the user manual!

I politely pushed back and asked to escalate to someone that can do something here as this reflects poorly on their customer service and would be something I'd caution others of before they invest in any other Drop products if this is the level of support they can expect to get.

I realize this is most likely going to be a dead end for me, but I don't see much choice else that I have except to keep politely asking to escalate until there's no where else I can go. I guess at that point, I'll ask Amir and any other review places I can find to add something to their posts cautioning others that they are SOL if the amp breaks, since it seems like the only way to force change these days, is to hit their bottom line.
 
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